Embodiments of the present invention relate to a non-volatile storage device, and more particularly to use of the non-volatile storage device in a system.
As computer systems continue to evolve with greater processing capabilities, a major bottleneck to improved system performance is the delay or latency associated with accessing requested information from a memory hierarchy. Latencies can be particularly high if information needs to be accessed from a mass storage device. Accordingly, various proposals exist for improving or increasing intermediate a between a processor and a mass storage device. For example, static random access memory (SRAM) is often closely coupled with a processor to act as a cache memory to store frequently requested information that can be rapidly accessed by the processor. Further, it has been proposed to reduce latencies by incorporating a so-called disk cache between a disk drive mass storage device and a processor so that read and write data may be provided to and from the processor via the intermediary disk cache.
It is anticipated that future systems and operating systems (OSs) for use in these systems may seek to reduce both latencies and delays associated with paging information in and out from memory. To this end, devices such as expanded or extended memory devices (EMDs), which may be external memory devices, may be coupled to a system to provide storage to act as an extended physical memory, allowing more virtual memory pages to be located in a lower than disk latency memory, thus reducing delays. Because such an external expanded memory device may be removed from one system and placed into another, upon powering down of the first system, the contents of the EMD will be flushed in order to ensure that no changes have been made that would corrupt the contents. Accordingly, even if the EMD is not removed from the system, on a next power up of the system, the EMD will not include any valid data. Thus the delays associated with accessing information from a mass storage device must occur until the EMD is filled, which may take many minutes, impacting performance.